PRESENTATION

City Chamber of Commerce

A little about incinerators

• Required to have air pollution controls– Federal Law - Clean Air Act 1970• Ended open burning at US Landfills• City Incinerators were required to install pollution

controls or stop operating

Incinerator Technology

• Mass Burn Waterwall Combustion Technology– How it works– What it does– Benefits of this technology vs. Land filling

How it works:

• Mass burn units– Waste is combusted without any preprocessing

• other than removal of items too large to go through the feed

– Refuse is placed on a grate– Grate moves through the combustor– Combustion air is supplied both below (underfire air) and

above (overfire air) the grate. – Range in size from 46 to 900 Mg/day (50 to 1,000 tpd) of waste

throughput per unit.• Mass burn waterwall

– Have water-filled tubes in the furnace walls that are used to recover heat for production of steam and/or electricity.

What it does: Explanation from AP-42

• Unprocessed waste gets delivered by an overhead crane to a feed hopper, – From there waste conveys to combustion chamber. – Facilities utilize reciprocating grates or roller grates to move

the waste through the combustion chamber.

• Combustor walls – constructed of metal tubes that contain circulating pressurized

water used to recover heat from the combustion chamber. – Heat is also recovered in the convective sections (i. e.,

superheater, economizer) of the combustor.

What it does: Explanation from AP-42

• Moving the waste through the combustion chamber: Grates– The grates typically include 3 sections.

• Initial grate section, referred to as the drying grate, the moisture content of the waste is reduced prior to ignition.

• second grate section, referred to as the burning grate, is where the majority of active burning takes place. • third grate section, referred to as the burnout or finishing grate, is where remaining combustibles in the waste

are burned.

• Combustion Process:– Underfire air plenums:

• supply of underfire air is added from beneath the grating. Usually to the individual grate sections through multiple plenums, which enhance the ability to control burning and heat release from the waste bed.

– Overfire air: • Injected through rows of high-pressure nozzles in the side walls of the combustor • This will oxidize fuel-rich gases from the bed and complete the combustion process. • **Proper design and operation of the overfire air system is critical for good mixing and burnout of organics in

the flue gas. Typically incinerators operate at 80 to 100% excess air.

– Flue gas exists combustor and goes through additional heat recovery sections to one or more air pollution control systems.

Mass Burn Combustion Material

• Waste Combustion: Ash– Bottom ash is taken from the finishing grate into:• Either a water-filled ash quench pit or ram discharger. • Moist ash is discharged to a conveyor system and

transported to an ash load-out area for later disposal.

Benefits of this Technology

• Future Outlook– Predominant technology in the existing population of

large MWCs– It is expected that over 50 percent of new units will be

MB/WW designs.• Heat Recovery– Combustor walls are constructed of metal tubes that

contain circulating pressurized water used to recover heat from the combustion chamber. • Economic value • Energy Production

Benefits of Incinerators

• Economic– Jobs Created• Trash Hauling – Trucking• Operations• Operational Support• Janitorial/Facility Maintenance

– Regulatory/Taxation– Privatization Possibility

Benefits of Incinerators

• Landfill space– Population growth– Combustion reduces volume of material going to

landfill

• Material use– Facilities take solid waste off trucks• No shredding or processing materials• Sorting likely

Benefits of Incinerators

• Heat Generated thru Combustion– Heat generated by burning waste:

• Direct Heating• Produce Steam• Generate Electricity

» Steam Turbine

– On Average, one ton of waste products 500 - 600 kilowatt-hours of electricity• Equivalent to energy produced by a:

– quarter-ton of coal– Or a barrel of oil

Ref: U.S. Energy Information Administration, Renewable Energy Annual 1996, Chapter 3, “Municipal Solid Waste Profile, (Washington, D.C., April 1997.)

Benefits of Incinerators

• So typically 500-600 kWh per ton of waste– Average Price of four cents per kWh

• Revenues per ton of solid waste = $20 or $30.00

• Our Situation: $2,400 to 3,600/day• 1 person creates 5 lbs of trash/day • 48,000 people of the city would roughly create 240,000 lbs/day.

120 tons/day (240,000 lb/2,000 lb/ton)

• This is actually on the lower range of incinerators according to ap 42.

Benefits of Incinerators

• Trash Disposal Fee’s– Possibility of additional waste pickup• Community contracting

• Federal Production Tax Credit– One cent per kWh available for MSW energy

producted

Incinerators - Considerations

• Environmental Impact– Air pollutants are created (in controlled manner)

– 1995, EPA ordered waste to energy facilities to meet maximum pollution control stanards» Significantly reduced emissions of dioxins, mercury, lead,

cadmium, hydrochloric acid, and particulates

“ EPA estimates that requirements reduced emissions of dioxins and furans from waste-to-energy plants by more than 99 percent; metals by more than 93 percent; and acid gases by more than 91 percent. “

U.S. EPA, Municipal Solid Waste: Electricity from Municipal Solid Waste, http://www.epa.gov/cleanenergy/energy-and-you/affect/municipal-sw.html/

Incinerators - Considerations• Solid Waste Generation – ASH

– contain any of the elements that were originally present in the waste.

– Good Note: MSW power plants reduce the need for landfill capacity because disposal of MSW ash requires less land area than does unprocessed MSW.

– However, ash may contain toxic materials– Steps must be taken to prevent toxic substances from migrating into ground-

water supplies. – Hazardous ash must be managed and disposed of as hazardous waste.

Depending on state and local restrictions, non-hazardous ash may be disposed of in a MSW landfill or recycled for use in roads, parking lots, or daily covering for sanitary landfills.

– Disposal Fees for Ash

Incinerators - Considerations

• Water Discharge/Water Usage– Use water in boilers and in cooling• Higher temperature discharge water

– Could harm» Aquatic life» Reduce Water Quality

• Noise

Benefit Comparison of Incineration to Land filling

Incinerators– Most incinerators sort the waste stream.

Therefore, more recycling of the waste stream takes place.

– Reduction of the amount of material that must be landfilled.

– Hazardous streams are more easily removed from the waste stream because of the additional sorting.

– smaller footprint than a comparably sized landfill.

– The waste that is "incinerated" is used to generate heat -- this heat is used to heat neighboring buildings (or neighboring tenants) and high quality steam (for electrical generation).

Landfills– Leachate collection and treatment on-

site. Because the landfill is designed and built to store waste, this is thought to be a safe containment of our garbage.

– Methane gas is collected at a number of municipal waste landfills and some landfills have diesel/gas blended fuel fired electrical generation stations built on them.

– Upon closing of a landfill, some beneficial usage of these land resources have been realized. Certain closed landfills have become golf courses, ski mountains, etc.

Disadvantage Comparison: Incineration to Land filling

Incinerators• When incinerating municipal waste, certain

pollutants will be emitted to the air. • Particulate (and PM10), • Carbon Dioxide, • Carbon Monoxide, • Metals (including Hg) • Hydrogen Chloride• Dioxins/Furans and certain organics.

• Hazardous materials sometimes pass sorting and are incinerated, emissions will go into the air.

• Pollutants in atmosphere will not be confined to a known area (compared to the known physical bounds of a landfill).

• Traffic around incinerator is significantly increased due to the heavy truck and waste hauler traffic.

• Public perception with a smoke stack.

Landfills• Leachate collection and treatment on-site.. • Municipal waste mixing with hazardous waste

steams find there way into municipal waste landfills, the contaminants can find their way into drinking water.

• Landfills are often constructed in low lying areas and built in cells that may encompass 50 to 150 acres (or more).

• They attract varmin, birds, bears and other not so attractive wildlife. They can have some odor that can often be detected outside the bounds of the property borders.

• Traffic around landfills can be significant -- especially during morning and early afternoon hours.

• Upon landfill closure, land use is extremely limited.

Wood County Landfill• The Wood County Solid Waste

Management District was created as a result of House Bill 592, passed in 1988. The bill created 52 Solid Waste Management Districts in Ohio.

“Our mission as a Solid Waste Management District is to assure there is sufficient capacity available to dispose of local waste and to implement programs to reduce, reuse, and recycle 50% of the waste that is generated by local businesses and residents. We are also required to ensure that 90% of the county residents have access to recycling, or to provide data that 25% (or more) of residents are actually participating in recycling programs.”

• According to district figures, an estimated 35,000 to 40,000 tons of waste is disposed outside the district annually.Ken Rieman, district director, last week said revenue from fees in 2010 reached approximately $782,000, but he is projecting it will only reach $600,000 this year based on collections the first two months of the year.

WASTE MATERIALS including recyclables, garbage, and refuse will be collected from 1 & 2 family dwellings on City streets per city ordinance once a week at the curb. Refuse/recycling collection is on a four day collection schedule.

Uncontrolled Emission RateChemical lb/ton G (mg/sec)PM 25.1 0.015813As 0.00437 2.75E-06Cd 0.0109 6.87E-06Cr 0.00897 5.65E-06Pb 0.213 0.000134SO2 3.46 0.00218HCl 6.4 0.004032CDD/CDF 0.00000167 1.05E-09NOX 3.56 0.002243CO 0.463 0.000292